ex. PTHectomy
Ca normally shields Na channels, lack of Calcium leads to rapid firing of channels, spontaneous action potentials
death by laryngospasm
PTHectomy results in less PTH and thus less calcium in the blood

how can colloid pressure affect the brain

lack of proteins in the blood leads to a low colloid pressure
low blood volume
osmotic force thus not sufficient
not enough blood to brain or coronary vessels

how does addisons lead to circulatory shock

hypoadrenalism, lack of aldosterone, less Na retained, not enough blood volume so less blood to tissues

denervation, and renervation
if 3 months, full
if 2 years, little function, muscle replaced by fat

can muscle cells regenerate

yes, with satellite cells

what is destroyed in mysasthenia gravis

ACh receptors, nicotinic, at skeletal NMJ

muscles affected first in myasthenia gravis?

muscles of the face, small number of receptors

removal of thymus in myasthenia gravis patient is helpful because

thumus makes antibodies that destroy receptors, by knocking out antibodies you can help

whole motor unit contracts as a ripple on the skin

fasciculation

denervated muscles begin to have spontaneous impulses

fibrillation

high cortisol leads to hyperglycemia and increased insulin. what should happen?

downregulation of insulin receptors

type of smooth muscle innervated by a single nerve ending; control exerted mainly by nerve signals from ANS

multiunit smooth muscle

type of smooth muscle where sheets function as a single unit; cells arranged in sheets or bundles with gap junctions forming electrical synapses, fibers from functional syncitium that contracts as large area at a time

visceral smooth muscle (single-unit)

similarities of smooth muscle with skeletal

actin and myosin in both
process activated by Ca, ATP ->ADP
cAMP can affect both (regulates passage of Ca through ion channels)
same strength, smooth muscle may be stronger

abnormal rhytmicity of pacemaker itself
shift of pacemaker from SA to other parts of heart
blocks at different points in transmission of impulse
abnormal pathways of impulse transmission through the heart
spontaneous generation of abnormal impulses in almost any part of the heart

heart block which slows impulses but all make it past the block

1st degree

heart block which some impulses make it past the block

2nd degree

complete heart block

3rd degree

difference between 2nd and 3rd degree heart blocks

3rd has p wave and QRS independent of each other on ECG
2nd degree block has the 2:1 or 3:1 ratio of p waves for each QRS

rhythm in which impulse travels around the heart without stopping

circus movement

two types of reentry

flutter
atrial fib

rapid but coordinated rentry

flutter

reentry in which erratic, high frequency but uncoordinated so no parts contract in unison

A fib

most common cause of clots

A fib, which can cause ventricular tachycardia

types of medicines to take if you are in A fib

blood thinners
rate control drugs
antiarrhythmic drugs

when contraction is premature and comes from somewhere other than SA node

ectopic foci

one form of tachycardia

ectopic focus becomes so irritable that it causes rhythmical contraction at rate faster than SA node and becomes pacemaker